Wednesday, December 23, 2015, 4:54 PM - On the morning of Friday, December 25, 2015, people all across Canada will be witness to an event that hasn't been seen since 1977 - a Christmas Day Full Moon.

From the forecast for who will see snow for Christmas, the country is somewhat divided, but provided there are clear skies, nearly everyone across Canada will be able to see a Christmas Day Full Moon - something that hasn't graced our skies since the very first Star Wars movie was in theatres for the first time, and won't be seen again until the year 2034.

What will our skies look like on Christmas Eve and Christmas morning?

Although many areas appear under cloud for Christmas Eve and Christmas morning, there is always the possibility of some local breaks in the cloud layers. Thus, it's still worth checking this out if you have a chance.

The Moon will appear full the entire night, of course, from when it rises Christmas Eve until it sets Christmas morning, however the exact timing of when it reaches its fullest - 11:12 UTC - will dictate who will be able see that point of the event.

Location

Time of Moonrise

Time of Moonset

Time of Full Moon

Vancouver

4:17 p.m.

7:52 a.m.

3:12 a.m.

Whitehorse

4:11 p.m.

9:38 a.m.

3:12 a.m.

Calgary

4:33 p.m.

8:21 a.m.

4:12 a.m.

Yellowknife

3:32 p.m.

9:25 a.m.

4:12 a.m.

Regina

4:56 p.m.

8:40 a.m.

5:12 a.m.

Winnipeg

4:27 p.m.

8:07 a.m.

5:12 a.m.

Thunder Bay

5:00 p.m.

8:29 a.m.

6:12 a.m.

Toronto

4:33 p.m.

7:33 a.m.

6:12 a.m.

Montreal

4:01 p.m.

7:14 a.m.

6:12 a.m.

Québec City

3:50 p.m.

7:09 a.m.

6:12 a.m.

Fredericton

4:33 p.m.

7:47 a.m.

7:12 a.m.

Charlottetown

4:18 p.m.

7:33 a.m.

7:12 a.m.

Halifax

4:25 p.m.

7:30 a.m.

7:12 a.m.

St. John's

4:01 p.m.

7:24 a.m.

7:42 a.m.

All times are expressed in the local time for each location.

The exact timing of when the Moon rises and sets is determined by what time zone a location is in, where that location is within its time zone, and the location's latitude. The Full Moon, however, happens at one particular moment that happens regardless of what time zone the observer is in. Thus it happens earlier in the west and later in the east. Note that for St. John's and much of the island of Newfoundland, the exact moment of the Full Moon will happen after the moon has set.

Truly rare?

Is this Christmas Day Full Moon really a rarity in our skies?

It's true that the last full moon was 32 years ago, and the next one won't happen for another 17 years after this.

However, pick any day of the year and you can find similar gaps between the years with a full moon on that specific day. Take a Boxing Day Full Moon as an example.

The last time there was a Full Moon on Boxing Day, for all of Canada's time zones, it was in 2004. The one before that, though, was way back in 1939 (the 1958 Dec 26 Full Moon took place at 3:54 UTC, which is still December 25 for all of Canada except Newfoundland). The next one won't be until 2042. So, that's certainly more rare than a Christmas Day Full Moon these days.
Still, a Christmas Full Moon is a rare enough occurrence that we will only see one or maybe two of these in our lifetime, so it's definitely worth checking out.

Miss it?

If the weather just won't cooperate for viewing on Christmas Eve or Christmas morning, but you have clearer skies overhead in the evening of the 25th, you can still check out this Christmas Full Moon. It won't be as full as it was before it set in the morning, but it will certainly be close enough that most probably won't notice the difference.

Is there enough of a difference to matter? Two views of the Full Moon on December 25, one before sunrise (left) and one after sunset (right). Credit: NASA's Scientific Visualization Studio, with notations by S. Sutherland